1. Managing Pupillary Block after Descemet Stripping Endothelial Keratoplasty
Dorota Tarnawska, MD
Dariusz Dobrowolski, MD
Dominika Janiszewska
Edward Wylegala, MD, PhD
Dept. of Ophthalmology, District Railway Hospital, Katowice, Poland

2. Authors do not have any financial interest or relationship to disclose

3. Purpose:
Pupillary block is the potential complication resulting from forward or backward iris movement causing by residual air bubble in Descemet Stripping Endothelial Keratoplasty (DSEK) eyes.
We described the management of pupillary block of two different mechanisms after DSEK.

4. Block mechanisms
Anterior block (A)– air prevents aqueous drainage through the iris – fluid collected behind the peripheral iris closes the angle.
Posterior block (P) – air behind the iris displaces it forward and sticks to the cornea. A P

5. Methods:
All patients with posterior air misdirection were treated with iris dilation and head positioning (lifting).
„Partial” blocks were also treated with head position.
Partial posterior block
Only inferior iris stuck to cornea
Treatment:
pupil dilation + head lifted at a 45º angle with reference to bed surface
gravitational block release

6. Methods: Partial posterior block Only superior iris is stuck to cornea
Treatment:
pupil dilation + head positioned at a 45º angle with reference to bed surface (with beard a few cm higher than head)
gravitational block release

7. Posterior block - air behind the iris pushes it forward and sticks to the cornea.
Case 1. Endothelial lenticle thinning – graft is compressed with air.
Case 2. Peripheral iris-graft touching (arrow).

8. Methods:
In eyes with ineffective head positioning surgical intervention was necessary:
in eyes with anterior pupillary block the excess of air was remove via paracenhtesis in pseudophakic and via pupil in aphakic eye.
in pseudophakic eyes with posterior pupillary block surgical synechiolysis with iridectomy was performed to decrease IOP.

9. Results:
Among 136 DSEK eyes in 23 (17%) air bubble misdirection was observed on 1-3 postoperative days.
In 18 eyes (13%) appropriate head positioning was an exclusive and effective treatment.
In 5 eyes (4%) additional interventions were necessary to break pupillary block.
In all surgically treated eyes pupillary block was successfully broken.
In 1 eye a fibrin-like membrane formation in the pupillary opening was observed.

10. Conclusions:
In the majority cases of air misdirection head positioning is a sufficient method for preventing pupillary block.
The remaining can be effectively treated surgically regarding of block mechanism.